High precision bondwire inductors are often required in the design of high-speed analog circuits. Wireless communications applications, for example, demand high performance radio frequency integrated circuits (RFICs). Often RFICs require on-chip inductors as circuit elements. A typical voltage controlled oscillator (VOC) design for RF transmission, for instance, requires an inductor and a capacitor in a tank circuit. When the inductor is a bondwire, as is typical in many RF oscillator designs, the variation in the geometrical configuration of the bondwire is approximately five to ten percent when a standard wirebonding process is used. This variation can be detrimental to the operational characteristics of the bondwire inductor.
In a typical wirebonding situation, an effort is made to place the die onto a package substrate exactly where needed. When the die is placed, there is generally a variation between the intended location and the actual location of the placement. This variation from ideal placement may differ from die to die. The main contributor to the geometric variation in wirebonds is due to these variations in die placement. Actual die placement can typically vary from the intended placement transversely plus/minus fifty microns, and as much as three or four degrees rotationally. This variation is generally sufficient to alter the characteristics of a wirebond inductor. After a die has been placed, automated wirebonding machinery uses alignment markers included on the die and/or package substrate in order to position wirebonds. This leaves the wirebond links and orientations subject to the variations in die placement, as the wirebonding is performed based on an assumption of exact placement in the intended location. Due to these and other problems, improved wirebonding accuracy and a reduction in wirebond variation due to variation in die placement would be useful and advantageous in the arts.